Having managed the successful launch of the serious and ambitious “House of Cards” in February, Netflix now turns to the edgy, titillating and disturbing with new series “Hemlock Grove,” which premieres this Friday, April 19th on the streaming site, the full 13-episode season going live all at once. While “House of Cards” was aimed at prestige-seeking audiences, the Eli Roth-produced horror series “Hemlock Grove” has slightly different aims — the new red band trailer below promises, in its warning, “mild fornication, fellatio, heavy cocaine use, lesbian necrophilia, violent hemorrhaging.” Early reviews suggest the show is not destined to be ranked by critics next to “House of Cards” as one of the finest of 2013 at year’s end, but in terms of viewership, boundary-pushing content tends to attract a far broader audience than nuanced political drama. Take a look: